1. Field of the Invention
The present invention concerns a process for depositing refractory metal silicide by the technique of vapor phase chemical deposition for the manufacture of integrated circuits.
2. Discussion of the Background
In the manufacture of integrated circuits, to produce interconnections in particular, it is necessary to be able to deposit polycristalline silicon, or refractory metals, which are better conductors, or even intermediate compounds of the type WSi.sub.x, for example, i.e. refractory metal silicides.
In well known manner, the following reaction is carried out: EQU WF.sub.6 +2SiH.sub.4 .fwdarw.WSi.sub.2 +6HF+H.sub.2
which can produce WSi.sub.2 from known precursors of W and Si. On the one hand, this technique has the disadvantage of producing large quantities of HF, which is detrimental for the pumps as well as for SiO.sub.2. On the other hand, the Applicant has established that WF.sub.6, in the presence of SiF.sub.4, may give no deposit whatsoever under usual conditions.